zinc displaces gold in seawater present int he form of gold (III) hydroxide. What mass of gold can be recovered if 20 moles of zinc are available?
To determine the mass of gold that can be recovered when zinc displaces gold in seawater, we need to use stoichiometry and the molar ratios between zinc and gold.
First, we need to balance the chemical equation for the reaction where zinc displaces gold:
Zn + Au(OH)₃ → Zn(OH)₂ + Au
The balanced equation shows that for every one mole of zinc, one mole of gold will be obtained.
Given that 20 moles of zinc are available, we can establish the following molar ratio:
20 moles of Zn : 20 moles of Au
Since the molar mass of gold is required to calculate the mass, it is necessary to know the specific form of gold present in seawater, as its compound Au(III) hydroxide does not naturally exist in seawater. However, assuming that the gold is present in a known compound, let's proceed with the calculation using the molar mass of gold, which is 196.97 g/mol.
Using the molar ratio from above, we can calculate the mass of gold:
Mass of gold = Number of moles of gold × Molar mass of gold
Mass of gold = 20 moles of Au × 196.97 g/mol
Mass of gold = 3,939.4 g
Therefore, 3,939.4 grams of gold can be recovered if 20 moles of zinc are available.